Parsing with DOM using
MSXML
Kanda Runapongsa
([email protected])
Dept. of Computer Engineering
Khon Kaen University
XML DOM
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The XML Document Object Model
(DOM) is a Programming Interface for
XML documents
It defines the way an XML document
can be accessed and manipulated
It is designed to be used with several
programming languages and any
operating system
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Introduction to DOM
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A program called an XML parser can
be used to load an XML document
into the memory
When the document is loaded, its
information can be retrieved and
manipulated by accessing the DOM
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Overview of DOM
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The DOM represents a tree view of
the XML document
The documentElement is the top-level
of the tree
This element has one or many
childNodes that represent the
branches of the tree
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The Microsoft XML Parser
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Supports JavaScript, VBScript, Perl,
VB, Java, C++ and more
Supports W3C XML 1.0, XML DOM,
and SAX
Supports DTD and XSD
The Microsoft XML parser is a COM
component that comes with Microsoft
Internet Explorer
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Creating an XML Document Object
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Javascript
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var xmlDoc = new
ActiveXObject("Microsoft.XMLDOM")
VBScript
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set xmlDoc =
CreateObject("Microsoft.XMLDOM")
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Loading an XML File
<script type="text/javascript"> var
xmlDoc = new
ActiveXObject("Microsoft.XMLDOM")
xmlDoc.async="false"
xmlDoc.load(“cdcatalog.xml")
// ....... processing the document goes
here </script>
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DOM Node
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The node object represents a node in
the node tree.
A node can be an element node, a
text node, or any other of the node
types
All of these node types have
properties and methods
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DOM Node Properties
Property
Description
attributes
Returns all attributes
childNodes
Returns a NodeList containing
all the child nodes
Returns the parent node
parentNode
firstChild
Returns the first child node for
this node
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DOM Node Properties
Property
Description
firstChild
Returns the first child node
lastChild
Returns the last child node
nextSibling
Returns the next sibling node
previousSibling Returns the previous sibling
node
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DOM Node Properties
Property
Description
nodeType
Returns the nodeType as
a number
nodeValue
Returns the value of this
node
ownerDocument Returns the root node of
the document
nodeName
Returns the nodeName
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DOM Node Methods
Method
Description
appendChild
(newChild)
Appends the node newChild
at the end of the child
nodees
hasChildNodes Returns true if this node has
()
any child nodes
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DOM Node Methods
Method
Description
insertBefore
(newNode,
refNode)
removeChild
(nodeName)
replaceChild
(newNode,
oldNode)
Inserts a new node,
newNode, before the
existing node refNode
Removes the specified
node, nodeName
Replaces the oldNode, with
the newNode
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Node Types
NodeType
Named Constants
1
ELEMENT_NODE
2
ATTRIBUTE_NODE
3
TEXT_NODE
4
CDATA_SECTION_NODE
5
ENTITY_REFERENCE_NODE
6
ENITY_NODE
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Node Types
NodeType
Named Constants
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PROCESSING_INSTRUCTION_N
ODE
COMMENT_NODE
9
DOCUMENT_NODE
10
DOCUMENT_TYPE_NODE
11
DOCUMENT_FRAGMENT_NODE
12
NOTATION_NODE
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DOM NodeList Object
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length: return the number of nodes in a
nodeList
item: return a specific node in the
nodeList
Examples:
xmlDoc.documentElement.childNodes.leng
th
xmlDoc.documentElement.childNodes.item
(2)
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DOM Elements
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tagName: return the tag name of a
node
getElementsByTagName: return the
value of a specified node
getAttribute: return an attribute’s
value
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DOM Attributes
name: return the name of an attribute
 Value: return the value of an attribute
 Example:
for each x in
xmlDoc.documentElement.attributes
document.write(x.name)
document.write(x.value)
next
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